Method of embossing



May 11, 1937. JENETT 2,080,276

METHOD OF EMBOSSING 7 Filed Dec. 22, 1934 lNVENTOR HJ 1r B vnilj ene AOR EY Patented May 11, 1937 t 7 2,080,276

UNITEDSTATES' PATENT oer-ice METHOD or Emiossme Henry Jenett, Demarest,N. .L, assignor to Celanese Corporation of America, a corporation ofDelaware Application December 22, 1934, Serial No. 758,727

3 claims.- (01. 101-32) This invention relates to the embossing ofcomheated dry, it set the imprint of the engraved posite materials suchas imitation leather, oil design in the paper surface.

cloth, etc. formed by coating a fabric or other Whenever it is desiredto change the design, a base material with a thermoplastic material, fornew steel roller is, of course, needed, but the 5 instance an organicderivative of cellulose. The paper roll remained and the designobliterated present invention is a continuation-impart of and redesignedby running hard against the new the invention described in applicationS. No. 732,- steel roller. These changes are limited, however. 996 filedJune 29, 1934. v due to the wear on the paper which when turned Anobject of the invention is the economic and down throws the ratio ofcircumferences off of .0 expeditious embossing of composite materialsand o e m pl Also as t m r decreases the construction of an efficientand inexpensive the a s c r y the Same Shaft and t mesh embossingdevice. Another object of the invenwith the gears of t embossing r011,bottom p tion is the construction ofa matrix roll for an. on ac o e w nPressure is p p a embossing device that isdurable, easily handled lywhenthin fabrics are being embossed. The

l5 and inexpensive. other objects of the invention paper c vered matrixroll ein f en r will appear from the following detailed descripia t rand s d throughout a v y avy tion and drawing. and must be handled bymeans of crane arms. As an aid in visualizing this invention one mod-Furthermore, as the Paper matrix Was driven y ification of a matrix rollwith its associated parts a gear off the steel roller, it wa necessaryto is shown in the drawing. In the drawing like it e p vi h paper roll wth its wn gear. reference numerals refer to the same or similar o t emand Switch the gear to e e elements in the various parts, matrix rollplaced on the device.

Fig. l'is a ,front view partially in section of a e-eeeldehce With yinvention then I orm part of an embossing device showing the emanassembled matrix r ll containing a core, bossing and matrix rolls inplac adapted to remain in the device, having a sur- Fig, 2 i a t a sv ithrough t matrix face member or shell adapted to fit on the core rollshell. and easily changeable, which surface member F 3 is a transverseview through the matrix preferably has a thermoplastic or thermosettingroll with shell removed, surfacing. to readily take the print of the en-0 Fig. 4 is a transverse view through a matrix graved roller. Further inaccordance with my roll with sh ll n place, invention I use such adevice to emboss a com- Prior to this invention machines used in em-.-Dos te material by a cold r011 method of embossing coated fabrics andthe like, generally bossineconsisted of one or moreengraved steelrollers This invention is applicable to the embossand a matrix roll madeof steel covered with ing of any suitable b material coated or im- 85paper or other tough, fibrous substance. In the pregnated with athermoplastic coating material case of a paper matrix,the most commonlyused, such as material containing organic derivatives 9. large number ofsheets of kraft paper are of cellulose, for instance, organic esters ofcellustacked on a mandrel, or steel core, compressed lose and celluloseethers. Examples of organic under extreme pressures and held in place byend esters of cellulose are cellulose acetate, cellulose 40 plates sothat the paper leaves are held in place. 'formate, cellulose propionateand cellulose butyr- The assembled steel core and paper body were atewhile examples of cellulose ethers are ethyl placed-in a lathe andturned down to a suitable cellulose, methyl cellulose and benzylcellulose. diameter, which must be at least the same as the The basematerial and the coating material may diameter of the steelengravedembossing roller be any suitable substance and may becompoundthat the matrix was'to be used against or the ed and joinedtogether in any suitable manner, diameter was such that thecircumference of the for instance, the materials and methods may bematrix roll was an uneven multiple of the ciremployed as described in U.S. applications No. cumference of the embossing roll such that the641,233, filed November 4, 1932, No. 671,642 filed design on both wouldregister. The paper roll May 18, 1933, No. 681,689 filed July 22, 1933,No. 50 was placed in the embossing machine, the steel 718,168 filedMarch 30, 1934 and No. 754,501 filed roller was run hard against it forfrom 2 to 4 November 23, 1934. a V hours or longer while the paper rollwas wetted The embossing process, for. which this invenso that the steelroll would displace the paper tion is most applicable is one in whichcold emto form a print of the embossing roll and, when bosslng rolls areemployed. The plastic mate- 5 rial surface with or I without apreheating is embossed with a cold,

tially the diameter of the embossing roll as no consideration need bemade for wear of the surface. It preferably tapers slightly toward oneend- Over 1: slightly tapered core a conical shell may be placed theconus, or taper corresponding with that of the core such that theassembly is a 'true cylinder.- The conical shell may be made eitherentirely of a suitable plastic material or from a plastic compositionsuperimposed on a metal shell, the latter being used preferably forstrength, wear, etc. as well as for'its superior heat transmittingproperties. The plastic material employed as, or on, -the shell may beany thermoplasticor thermosetting material having a higher melting orsoftening point than the thermoplastic material employed as the coatingon the material being embossed, for instance, metal alloys as Rosemetal, etc. although not generally classified as a plastic, syntheticresinous materials of the phenol-formaldehyde type, formaldehyde-ureatype, vinyl resin type and formaldehyde phthalic type, etc.

In the drawing is shown a matrix roll coming within this invention. Inthe drawing I is the main frame of an embossing device. The main frame.I may be provided with bearings 2 formed integral therewith or separatetherefrom. In the bearings 2 may be journaled a shaft 3 which is formedas the outer ends of a core 4. The core 4 may be made of metal or othersuitable material and its outer surface is preferably slightly taperedor conical. Grooves 5 may be formed in or be cut into the outer surfaceof the core 4 parallel to its axis.

The shell 6 may be formed having a cylindrical outer surface and atapered inner surface to correspond with the taper on the core 5.Suitable tongues may be formed on the inner surface of the shell thatsubstantially'flt the grooves 5. A slight amount of play may be allowedthat may be taken up by shims, wedges, etc. to more accurately positionthe shell upon the core. One tongue and groove may or may not be largerthan the remaining ones for the purpose of properly positioning theshell with respect to the remaining elements of the device. If ametallic shell is employed it may contain a coating 8 of a mouldablematerial such as a resin, etc. After the shell is placed on the core itmay be held A pair of adjustable bearings 9 may be provided to operatein guideway Ill of the main frame. Any suitable means may be employedfor regulating the downward pressure on the bearings, such means may besprings, screws, hydraulic pistons or other suitable means. Journaled inthe bearings 9 is a roll l l formed of steel or other suitable materialand having an engraved surface that may be engraved in any suitabledesign.

On the ends of the core 3 and the roll ll may be gears l2 and I3 thatinnermesh. The gear I2 is preferably driven and imparts rotation to thegear l3 and roll ll.

Both roll II and core 4 may be hollow and connected through the endsthrough a union or other device to a source of a cooling medium or ifdesired to'a heating medium.

In operation an embossing roll II is placed in the device and a shellv 8is slipped on the core 4. Heat may be applied to both rolls. Therollsare held hard against each other and the device run for a few-minutes,after which the heating medium is withdrawn and a cooling medium causedto chill both rolls. In place of changing the design on the matrix rollwith each change of the engraved roll a separate matrix roll shell maybe formed for each embossing roll and the sets changed. This is madepossible by the slight adjustment at the tongue and grooves and by theendwise movement by means of collars l4 and I5.

As illustrations and not as limitations the following examples aregiven.

Example I The tapering shell, preferably made from steel or some othertenacious metal which is a good conductor of cold temperatures, iscoated with a layer of a reasonably soft metal alloy, for instance, Rosemetal or other antimony alloy, that will take an imprint of theembossing roller. The roll is kept hot while working the rolls togetherfor five minutes, then chilled. The metal alloy is a good conductor. Itwithstands considerable pressure and does not flow unless heated andwhile the imprint is sharp it does not cut the fabric being embossed.The matrix may be reworked by running it against another-heatedembossing roll.

- Example If Example I is repeated except that the shell is covered witha thermoplastic resinous coating such as glyptal resin. The resinouscoating after being chilled gives a perfect replica of the embossingroll. 4

The coated fabric preferably preheated may be passed between the chilledembossing rollers whereby a design is pressed in the coating materialand the plastic coating set to produce a permanent design in thematerial. The shell of plastic material on the matrix roll when employedin a cold embossing processmay last indefinitely although made ofmaterial much softer than steel. No long periods of working are requiredto change a design on the matrix roll when same are coated material andwear during almost negligible.

It is to be understood that the above detailed description and drawingare merely givenv by changing of design is of a fabric coated with athermoplastic material which comprises passing cool composite materialbetween an embossing member and a matrix member both of which arepositively cooled.

with a thermoplastic 2. A method of embossing composite materials 3. Amethod of embossing composite materials containing a fabric coated withan organic decontaining a; fabric coated with cellulose acetate rivativeof cellulose which comprises passing cool which comprises passing coolcomposite material composite material between an embossing membetween anembossing member and a matrix 5 her-and a matrix member both of whichare posimember both of which are positively cooled.

tiyely cooled. HENRY JENETT.

